Problems
practice
- The Davisson-Germer experiment that first demonstrated the wave nature of matter used electrons accelerated to 54 V.
- Determine the energy of the electrons in…
- electronvolts
- joules
- How fast were the electrons moving in this experiment?
- What momentum did these electrons have?
- Determine the wavelength of these electrons.
- What form of electromagnetic radiation has the same wavelength as the value you calculated in part d.?
- Repeat the Davisson-Germer experiment using a pitching machine that launches 145 g baseballs with a speed of 100 m/s at two doors separated by one meter. Determine…
- the momentum of the baseballs
- the de Broglie wavelength of the baseballs
- the distance in light years to the "screen" that would result in "bright" interference fringes separated by a distance greater than the diameter of one baseball (7.4 cm)
- As a first approximation, an electron in a hydrogen atom can be said to orbit the nucleus at a distance of 0.0529 nm. Determine the following quantities for an electron that just fits in the circumference of this orbit…
- its de Broglie wavelength in meters
- its momentum in kg m/s
- its kinetic energy in electronvolts
- its electric potential energy in electronvolts (watch the sign)
- its total energy in electronvolts
- Write something completely different.
conceptual
- Matter has both particle and wave properties.
- Why don't we notice the particle nature of matter in our everyday experience?
- What experimental evidence do we have to show that matter is composed of particles (atoms, molecules, ions)?
- Why don't we notice the wave nature of matter in our everyday experience?
- What experimental evidence do we have to show that elementary particles can behave like waves?
- Light and other forms of electromagnetic radiation have both particle and wave properties. Answer the following questions. Provide an example of a device, event, phenomenon, or process that can be used to demonstrate each of the two different models of light. Choose examples from common experience. No fancy laboratory experiments or abstract textbook situations.
- What evidence do we have that light is a wave?
- What evidence do we have that light is composed of particles (photons)?